1. Field of the Invention
The present invention relates to a technique that shields an object and some space volume from an external observer so as not to be detected, and more particularly, to an electromagnetic cloaking structure and a method for manufacturing the same.
2. Description of the Related Art
There are many reports on attempts to shield an object from electromagnetic waves (including visible light). The observer detects a target object, using disturbance in electromagnetic waves caused by the scattering, reflection, or absorption of the electromagnetic waves which are incident on the target object. For example, stealth technology or a low radar cross-section structure has been known as a method for preventing the detection. As another method, for example, a method has been known which controls the material parameters of a space such that electromagnetic waves travel around the target object to be shielded.
For example, JP2008-23517A discloses an electromagnetic cloaking method which constructs a plurality of shielding volume elements around volume that can be shielded and uses anisotropic material parameters as the volume elements.
J. Li et al., “Hiding under the Carpet: A New Strategy for Cloaking” Physical Review Letters, 101, 203901, 2008 discloses a method that makes an object invisible, using quasi-conformal mapping, an isotropic medium, and reflective cloaking. However, this technique relates to reflective cloaking and does not disclose transmissive cloaking. In addition, U. Leonhardt, “Optical Conformal Mapping”, Science, Vol. 312, p. 1777, 2006 and Y. Ma et al., “First experimental demonstration of an isotropic electromagnetic cloak with strict conformal mapping”, Scientific Report, 02182, 2013 disclose a technique that can make an object invisible, using quasi-conformal mapping, an isotropic medium, and transmissive cloaking.